The Louisville Slugger TPS Catalyst FP72C Fastpitch Bat features multiple layers of aerospace grade graphite and S-glass fibers that are embedded in a specially designed toughened epoxy resin. Each layer is precisely positioned at an angle determined by our exclusive, computer designed pattern. This results in a bat with optimum combination of performance and durability. Composite design. Balanced swing weight. Synthetic grip, 7/8" standard handle. ASA, USSSA, ISA, ISF, NSA approved. -8 oz. weight ratio.